GBA engineers identified 54 potential Facility Improvement Measures (FIMs) in this retro-commissioning project in a major Northeastern city, including 27 low-cost measures with projected annual savings of $108,000. The implementation cost to achieve this level of savings was less than $25,000.
Implemented FIMs included:
- On-off scheduling of an ancillary kitchen exhaust fan, saving $6,000 per year and improving building pressurization.
- Calibrating differential pressure sensors, restoring variable flow to a heating hot water system.
- Correcting the sequencing of steam control valves.
- Removing defunct steam preheat coils, reducing air system pressure drop and saving $18,000 per year in fan energy.
- Correcting air-side economizer operation, reducing cooling energy.
- Adding pilot positioners to a chilled water bypass valve, enabling the minimum pump speed to be reduced (projected annual savings, $22,000).
- Repairing leaking steam control valves to reduce steam consumption.
- Performing scheduled service to hot water and cold water pumps.
Several deferred capital improvement measures were also identified, including lighting retrofits, conversion to variable flow kitchen exhaust, chiller replacement, and other projects totaling an $8 million investment with a 5.4 year payback.
